The magnetic potential energy stored in a certain inductor is `25mJ`, when the current in the inductor is `60 mA`. This inductor is of inductance

Options

A. 0.138 H
B. 138.88 H
C. 1.389 H
D. 13.89 H

Answer

D

Explanation

magnetic potential energy stored in an inductor is given by
`U = 1/2 LI^2 rArr 25 xx 10^(-3) = 1/2 xx L xx (60 xx 10^(-3))^2`
`L = (25 xx 2 xx 10^6 xx 10^(-3))/(3600) = 500/36 = 13.89 H`